Since finding a few of them recently, I've been keeping an eye out for old folding rulers when I'm out and about; I think they're just great looking, as well as a treat to use. This is a Stanley model 36 1/2" -- twelve inches unfolded, with a brass caliper that extends another five inches. There remains brass pin near the opening end which locks into the opposite side to hold it closed. 

6 3/4" l x 1 3/8" w x 1/8" d when folded. I have not touched either the wood or brass, but think the later would shine up some if desired. Very good condition.